Provided is a hydraulic hammering device that is capable of sufficiently transmitting hammering force to bedrock while further strengthening the cushioning action and suppressing equipment damage. The present hydraulic hammering device is provided with: a pushing piston (4) that is disposed immediately behind a transmission member (2), and has a lower propulsive force than a device body (1); a damping piston (5) that is positioned behind the pushing piston (4) so as to slide forward and backward therewith, and has a greater propulsive force than the device body (1); direction-restricting means (8, 9) that are provided in a high-pressure circuit (6) between a fluid supply source (P) and a fluid pushing chamber (41) and damping chamber (51), to which fluid for providing propulsive force to the pistons (4, 5) is supplied, said direction-restricting means permitting the inflow of fluid from the fluid supply source (P) to the chambers (41, 51) while restricting the outflow of fluid from the chambers (41, 51) to the fluid supply source (P); and a variable throttle (10) that is provided in a drain circuit (7) for discharging, to a tank (T), fluid leaking from the location of sliding contact.